STOCKHOLDERS' EQUITY - GSR Agreement (Details) - tZero.com, Inc. $ in Millions	Apr. 01, 2020 USD ($) shares
Class of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction \| shares	508,710
Number of shares sold in transaction as percentage of total shares issued and outstanding	0.50%
Total consideration received from sale of stock \| $	$ 5.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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